Currently, headsets are widely applied to enjoy music and videos. When a stereo signal is replayed by a headset, an effect of head orientation often appears, causing an unnatural listening effect. Researches show that, the effect of head orientation appears because: 1) The headset directly transmits, to both ears, a virtual sound signal that is synthesized from left and right channel signals, where unlike a natural sound, the virtual sound signal is not scattered or reflected by the head, auricles, body, and the like of a person, and the left and right channel signals in the synthetic virtual sound signal are not superimposed in a cross manner, which damages space information of an original sound field, 2) The synthetic virtual sound signal lacks early reflection and late reverberation in a room, thereby affecting a listener in feeling a sound distance and a space size.
To reduce the effect of head orientation, in the prior art, data that can express a comprehensive filtering effect from a physiological structure or an environment on a sound wave is obtained by means of measurement in an artificially simulated listening environment. A common manner is that, a head related transfer function (HRTF) is measured in an anechoic chamber using an artificial head, to express the comprehensive filtering effect from the physiological structure on the sound wave. As shown in FIG. 1, cross convolution filtering is performed on input left and right channel signals sl(n) and sr(n), to obtain virtual sound signals sl(n) and sr(n) that are separately output to left and right ears, where:sl(n)=conv(hθll(n),sl(n))+conv(hθrl(n),sr(n))sr(n)=conv(hθlr(n),sl(n))+conv(hθrr(n),sr(n)),where conv(x,y) represents a convolution of vectors x and y, hθll (n) and hθlr(n) are respectively HRTF data from a simulated left speaker to left and right ears, and hθrl(n) and hθrr(n) are respectively HRTF data from a simulated right speaker to left and right ears. However, in the foregoing manner, to obtain the virtual sound signal, convolution needs to be separately performed on the left and right channel signals, which causes impact on original frequencies of the left and right channel signals, thereby generating a coloration effect, and also increasing calculation complexity.
In the prior art, stereo simulation is further performed, using binaural room impulse response (BRIR) data in replacement of the HRTF data, on signals that are input from left and right channels, where the BRIR data further includes the comprehensive filtering effect from the environment on the sound wave. Although the BRIR data has an improved stereo effect compared with the HRTF data, calculation complexity of the BRIR data is higher, and the coloration effect still exists.